As I have a mixture of DVD and Blu-Ray covers in my collection (with different aspect ratios of course) I think it would be an improvement to have some kind of auto-sizing of the window frame according to the cover size. Currently I can have either top&bottom white frames on Blu-Ray covers or left&right white frames on DVD covers.

Of course the same issue exists in the regular ftont and back image views embedded in the layouts, but I can't imagine a solution for that...